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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * accompanied this code).
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package javax.swing.text;

import java.io.Serializable;

This class encapsulates a single tab stop (basically as tab stops
are thought of by RTF). A tab stop is at a specified distance from the
left margin, aligns text in a specified way, and has a specified leader.
TabStops are immutable, and usually contained in TabSets.

Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans™
has been added to the java.beans package. Please see XMLEncoder. /**
 * This class encapsulates a single tab stop (basically as tab stops
 * are thought of by RTF). A tab stop is at a specified distance from the
 * left margin, aligns text in a specified way, and has a specified leader.
 * TabStops are immutable, and usually contained in TabSets.
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 */
public class TabStop implements Serializable {

    
Character following tab is positioned at location. /** Character following tab is positioned at location. */
    public static final int ALIGN_LEFT    = 0;
    
Characters following tab are positioned such that all following
characters up to next tab/newline end at location. /** Characters following tab are positioned such that all following
     * characters up to next tab/newline end at location. */
    public static final int ALIGN_RIGHT   = 1;
    
Characters following tab are positioned such that all following
characters up to next tab/newline are centered around the tabs
location. /** Characters following tab are positioned such that all following
     * characters up to next tab/newline are centered around the tabs
     * location. */
    public static final int ALIGN_CENTER  = 2;
    
Characters following tab are aligned such that next
decimal/tab/newline is at the tab location, very similar to
RIGHT_TAB, just includes decimal as additional character to look for.
/** Characters following tab are aligned such that next
     * decimal/tab/newline is at the tab location, very similar to
     * RIGHT_TAB, just includes decimal as additional character to look for.
     */
    public static final int ALIGN_DECIMAL = 4;
    public static final int ALIGN_BAR     = 5;

    /* Bar tabs (whatever they are) are actually a separate kind of tab
       in the RTF spec. However, being a bar tab and having alignment
       properties are mutually exclusive, so the reader treats barness
       as being a kind of alignment. */

    public static final int LEAD_NONE      = 0;
    public static final int LEAD_DOTS      = 1;
    public static final int LEAD_HYPHENS   = 2;
    public static final int LEAD_UNDERLINE = 3;
    public static final int LEAD_THICKLINE = 4;
    public static final int LEAD_EQUALS    = 5;

    
Tab type. /** Tab type. */
    private int alignment;
    
Location, from the left margin, that tab is at. /** Location, from the left margin, that tab is at. */
    private float position;
    private int leader;

    
Creates a tab at position pos with a default alignment
and default leader.
/**
     * Creates a tab at position <code>pos</code> with a default alignment
     * and default leader.
     */
    public TabStop(float pos) {
        this(pos, ALIGN_LEFT, LEAD_NONE);
    }

    
Creates a tab with the specified position pos,
alignment align and leader leader.
/**
     * Creates a tab with the specified position <code>pos</code>,
     * alignment <code>align</code> and leader <code>leader</code>.
     */
    public TabStop(float pos, int align, int leader) {
        alignment = align;
        this.leader = leader;
        position = pos;
    }

    
Returns the position, as a float, of the tab.
Returns:
the position of the tab/**
     * Returns the position, as a float, of the tab.
     * @return the position of the tab
     */
    public float getPosition() {
        return position;
    }

    
Returns the alignment, as an integer, of the tab.
Returns:
the alignment of the tab/**
     * Returns the alignment, as an integer, of the tab.
     * @return the alignment of the tab
     */
    public int getAlignment() {
        return alignment;
    }

    
Returns the leader of the tab.
Returns:
the leader of the tab/**
     * Returns the leader of the tab.
     * @return the leader of the tab
     */
    public int getLeader() {
        return leader;
    }

    
Returns true if the tabs are equal.
Returns:
true if the tabs are equal, otherwise false/**
     * Returns true if the tabs are equal.
     * @return true if the tabs are equal, otherwise false
     */
    public boolean equals(Object other)
    {
        if (other == this) {
            return true;
        }
        if (other instanceof TabStop) {
            TabStop o = (TabStop)other;
            return ( (alignment == o.alignment) &&
                     (leader == o.leader) &&
                     (position == o.position) );  /* TODO: epsilon */
        }
        return false;
    }

    
Returns the hashCode for the object.  This must be defined
here to ensure 100% pure.
Returns:
the hashCode for the object/**
     * Returns the hashCode for the object.  This must be defined
     * here to ensure 100% pure.
     *
     * @return the hashCode for the object
     */
    public int hashCode() {
        return alignment ^ leader ^ Math.round(position);
    }

    /* This is for debugging; perhaps it should be removed before release */
    public String toString() {
        String buf;
        switch(alignment) {
          default:
          case ALIGN_LEFT:
            buf = "";
            break;
          case ALIGN_RIGHT:
            buf = "right ";
            break;
          case ALIGN_CENTER:
            buf = "center ";
            break;
          case ALIGN_DECIMAL:
            buf = "decimal ";
            break;
          case ALIGN_BAR:
            buf = "bar ";
            break;
        }
        buf = buf + "tab @" + String.valueOf(position);
        if (leader != LEAD_NONE)
            buf = buf + " (w/leaders)";
        return buf;
    }
}